From b97c97941f0bb2de86f871e4ef3ac24f483c170a Mon Sep 17 00:00:00 2001 From: AJ ONeal Date: Wed, 9 Dec 2020 05:01:29 -0700 Subject: [PATCH] suggest @root/walk --- README.md | 270 +++++++++++++++++++++++++++--------------------------- 1 file changed, 135 insertions(+), 135 deletions(-) diff --git a/README.md b/README.md index 9a1595b..3472e9a 100644 --- a/README.md +++ b/README.md @@ -1,60 +1,66 @@ -node-walk -==== +# 2021 Update -| Sponsored by [ppl](https://ppl.family) +Consider using [`@root/walk`](https://npmjs.org/package/@root/walk) instead. + +I created `walk` quite literally a decade ago, in the Node v0.x days. +Back then using an EventEmitter seemed like the thing to do. Nowadays, +it seems a bit overkill for the simple task of walking over directories. + +There's nothing wrong with `walk` - it's about the same as it was 10 years ago - +however, at only 50 lines of code long, `@root/walk` is much simpler and much faster. + +# node-walk + +| a [Root](https://rootprojects.org) project nodejs walk implementation. This is somewhat of a port python's `os.walk`, but using Node.JS conventions. - * EventEmitter - * Asynchronous - * Chronological (optionally) - * Built-in flow-control - * includes Synchronous version (same API as Asynchronous) +- EventEmitter +- Asynchronous +- Chronological (optionally) +- Built-in flow-control +- includes Synchronous version (same API as Asynchronous) As few file descriptors are opened at a time as possible. This is particularly well suited for single hard disks which are not flash or solid state. -Installation ----- +## Installation ```bash npm install --save walk ``` -Getting Started -==== +# Getting Started ```javascript -(function () { - "use strict"; +'use strict'; - var walk = require('walk'); - var fs = require('fs'); - var walker; +var walk = require('walk'); +var fs = require('fs'); +var walker; +var options = {}; - walker = walk.walk("/tmp", options); +walker = walk.walk('/tmp', options); - walker.on("file", function (root, fileStats, next) { - fs.readFile(fileStats.name, function () { - // doStuff - next(); - }); - }); - - walker.on("errors", function (root, nodeStatsArray, next) { +walker.on('file', function (root, fileStats, next) { + fs.readFile(fileStats.name, function () { + // doStuff next(); }); +}); - walker.on("end", function () { - console.log("all done"); - }); -}()); +walker.on('errors', function (root, nodeStatsArray, next) { + next(); +}); + +walker.on('end', function () { + console.log('all done'); +}); ``` -Common Events ------ +## Common Events All single event callbacks are in the form of `function (root, stat, next) {}`. @@ -63,16 +69,15 @@ All multiple event callbacks callbacks are in the form of `function (root, stats All **error** event callbacks are in the form `function (root, stat/stats, next) {}`. **`stat.error`** contains the error. -* `names` -* `directory` -* `directories` -* `file` -* `files` -* `end` -* `nodeError` (`stat` failed) -* `directoryError` (`stat` succedded, but `readdir` failed) -* `errors` (a collection of any errors encountered) - +- `names` +- `directory` +- `directories` +- `file` +- `files` +- `end` +- `nodeError` (`stat` failed) +- `directoryError` (`stat` succedded, but `readdir` failed) +- `errors` (a collection of any errors encountered) A typical `stat` event looks like this: @@ -95,63 +100,60 @@ A typical `stat` event looks like this: type: 'file' } ``` -Advanced Example -==== +# Advanced Example Both Asynchronous and Synchronous versions are provided. ```javascript -(function () { - "use strict"; +'use strict'; - var walk = require('walk'); - var fs = require('fs'); - var options; - var walker; +var walk = require('walk'); +var fs = require('fs'); +var options; +var walker; - options = { - followLinks: false - // directories with these keys will be skipped - , filters: ["Temp", "_Temp"] - }; +options = { + followLinks: false, + // directories with these keys will be skipped + filters: ['Temp', '_Temp'], +}; - walker = walk.walk("/tmp", options); +walker = walk.walk('/tmp', options); - // OR - // walker = walk.walkSync("/tmp", options); +// OR +// walker = walk.walkSync("/tmp", options); - walker.on("names", function (root, nodeNamesArray) { - nodeNamesArray.sort(function (a, b) { - if (a > b) return 1; - if (a < b) return -1; - return 0; - }); +walker.on('names', function (root, nodeNamesArray) { + nodeNamesArray.sort(function (a, b) { + if (a > b) return 1; + if (a < b) return -1; + return 0; }); +}); - walker.on("directories", function (root, dirStatsArray, next) { - // dirStatsArray is an array of `stat` objects with the additional attributes - // * type - // * error - // * name +walker.on('directories', function (root, dirStatsArray, next) { + // dirStatsArray is an array of `stat` objects with the additional attributes + // * type + // * error + // * name + next(); +}); + +walker.on('file', function (root, fileStats, next) { + fs.readFile(fileStats.name, function () { + // doStuff next(); }); +}); - walker.on("file", function (root, fileStats, next) { - fs.readFile(fileStats.name, function () { - // doStuff - next(); - }); - }); +walker.on('errors', function (root, nodeStatsArray, next) { + next(); +}); - walker.on("errors", function (root, nodeStatsArray, next) { - next(); - }); - - walker.on("end", function () { - console.log("all done"); - }); -}()); +walker.on('end', function () { + console.log('all done'); +}); ``` ### Sync @@ -166,7 +168,7 @@ I don't think I can prevent the `process.nextTick()` that `EventEmitter` calls. ```javascript (function () { - "use strict"; + 'use strict'; var walk = require('walk'); var fs = require('fs'); @@ -183,89 +185,88 @@ I don't think I can prevent the `process.nextTick()` that `EventEmitter` calls. if (a < b) return -1; return 0; }); - } - , directories: function (root, dirStatsArray, next) { + }, + directories: function (root, dirStatsArray, next) { // dirStatsArray is an array of `stat` objects with the additional attributes // * type // * error // * name next(); - } - , file: function (root, fileStats, next) { + }, + file: function (root, fileStats, next) { fs.readFile(fileStats.name, function () { // doStuff next(); }); - } - , errors: function (root, nodeStatsArray, next) { + }, + errors: function (root, nodeStatsArray, next) { next(); - } - } + }, + }, }; - walker = walk.walkSync("/tmp", options); + walker = walk.walkSync('/tmp', options); - console.log("all done"); -}()); + console.log('all done'); +})(); ``` -API -==== +# API Emitted Values - * `on('XYZ', function(root, stats, next) {})` +- `on('XYZ', function(root, stats, next) {})` - * `root` - the containing the files to be inspected - * *stats[Array]* - a single `stats` object or an array with some added attributes - * type - 'file', 'directory', etc - * error - * name - the name of the file, dir, etc - * next - no more files will be read until this is called +- `root` - the containing the files to be inspected +- _stats[Array]_ - a single `stats` object or an array with some added attributes + - type - 'file', 'directory', etc + - error + - name - the name of the file, dir, etc +- next - no more files will be read until this is called Single Events - fired immediately - * `end` - No files, dirs, etc left to inspect +- `end` - No files, dirs, etc left to inspect - * `directoryError` - Error when `fstat` succeeded, but reading path failed (Probably due to permissions). - * `nodeError` - Error `fstat` did not succeeded. - * `node` - a `stats` object for a node of any type - * `file` - includes links when `followLinks` is `true` - * `directory` - **NOTE** you could get a recursive loop if `followLinks` and a directory links to its parent - * `symbolicLink` - always empty when `followLinks` is `true` - * `blockDevice` - * `characterDevice` - * `FIFO` - * `socket` +- `directoryError` - Error when `fstat` succeeded, but reading path failed (Probably due to permissions). +- `nodeError` - Error `fstat` did not succeeded. +- `node` - a `stats` object for a node of any type +- `file` - includes links when `followLinks` is `true` +- `directory` - **NOTE** you could get a recursive loop if `followLinks` and a directory links to its parent +- `symbolicLink` - always empty when `followLinks` is `true` +- `blockDevice` +- `characterDevice` +- `FIFO` +- `socket` Events with Array Arguments - fired after all files in the dir have been `stat`ed - * `names` - before any `stat` takes place. Useful for sorting and filtering. - * Note: the array is an array of `string`s, not `stat` objects - * Note: the `next` argument is a `noop` +- `names` - before any `stat` takes place. Useful for sorting and filtering. - * `errors` - errors encountered by `fs.stat` when reading ndes in a directory - * `nodes` - an array of `stats` of any type - * `files` - * `directories` - modification of this array - sorting, removing, etc - affects traversal - * `symbolicLinks` - * `blockDevices` - * `characterDevices` - * `FIFOs` - * `sockets` + - Note: the array is an array of `string`s, not `stat` objects + - Note: the `next` argument is a `noop` + +- `errors` - errors encountered by `fs.stat` when reading ndes in a directory +- `nodes` - an array of `stats` of any type +- `files` +- `directories` - modification of this array - sorting, removing, etc - affects traversal +- `symbolicLinks` +- `blockDevices` +- `characterDevices` +- `FIFOs` +- `sockets` **Warning** beware of infinite loops when `followLinks` is true (using `walk-recurse` varient). -Comparisons -==== +# Comparisons Tested on my `/System` containing 59,490 (+ self) directories (and lots of files). The size of the text output was 6mb. `find`: - time bash -c "find /System -type d | wc" - 59491 97935 6262916 +time bash -c "find /System -type d | wc" +59491 97935 6262916 real 2m27.114s user 0m1.193s @@ -295,12 +296,11 @@ Note that `find.js` omits the start directory In conclusion node.js asynchronous walk is much slower than regular "find". -LICENSE -=== +# LICENSE `node-walk` is available under the following licenses: - * MIT - * Apache 2 +- MIT +- Apache 2 Copyright 2011 - Present AJ ONeal